#define  _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include<stdlib.h>
int main() {
    int a, b, c;
    while (scanf("%d%d%d", &a, &b, &c) != EOF) {
        if (a + b > c && a + c > b && b + c > a && abs(a - b) < c && abs(a - c) < b && abs(b - c) < a) {
            if (a == b && a == c) {
                printf("Equilateral triangle!\n");
            }
            else if (a == b || a == c || b == c) {
                printf("Isosceles triangle!\n");
            }
            else {
                printf("Ordinary triangle!\n");
            }
        }
        else {
            printf("Not a triangle!\n");
        }
    }
    return 0;
}